C3D Mini direct disconnect after starting jobfile (Latest Lightburn on Win10)


I purchased a C3D Mini last februari, and the board has functioned ok till last week in a K40.

It started to disconnect (status disconnected in LB) on USB almost right after a job start.
The board was running the default smoothie it came with, all the time and i can’t seem to figure out the problem.

To start with, i never used the blue usb cable that came with the K40 (bin it) and the cable i use worked fine. To start troubleshooting i tried good usb cables, different (pc, backside, onboard) usb ports, also on a different pc. the problem stayed the same.

Then i changed the firmware to GRBL-LPC, could configure the board in Lightburn, it homed but same problem on running files (no matter vector engrave/cut, raster engrave): it disconnects right after start of the job.

It’s also not “in the file”, i tried others and created new ones.

Someone had this problem too and has a solution?

Hi Patrick,

Is your board isolated from the chassis using nylon stand offs/screws? Which OS are you using? OS updates can cause issues with drivers and/or reset power save settings also. Some common and known issues are covered in FAQ: USB Dropouts and Brownouts